Max-Thrust Double Trouble Balsa Pro-Built Series User manual

Instruction Manual

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Warning:
This radio controlled model is not a toy. It requires skill to y and is not recommended for use by
beginners without assistance from an experienced model pilot. It should not be operated by children
without the supervision of a suitably experienced adult.
Max-Thrust reserves the right to modify the specication of this model at any time.
Safety Precautions
1. Do not attempt to repair or modify this aircraft with non-factory parts.
2. Never y this model over roads, railway lines, near to power lines, airports, do not y this model in
excessively strong winds, in the rain, or thunderstorms.
3. Do not y or launch the model towards people.
4. Keep hands and face away from rotating propeller at all times.
5. We strongly recommend that all xings and fasteners used in the construction of this model are
checked regularly for integrity. Failure to do so could cause a crash, injury to yourself or others around
you.
6. We only recommend the use of 2.4GHz radio equipment with this model.
Disclaimer
1. This radio controlled model is not a toy. Used incorrectly it is capable of inicting serious injury to
persons or damage to property. The owner/pilot assumes all responsibility for any damage to persons or
property resulting from the use of this product.
2. The manufacturer and distributor decline all responsibility for any liability arising from use of this
product.
3. It is very important that you follow all instructions for assembling and setting up of this model. Failure to
do so could result in a loss of control and possibly a crash
Statement

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Tools:
Philips Screwdriver Medium
Philips Screwdriver Small
Modelling Knife and Spare Blades
3mm Allen Key
2mm Allen Key
30 Minute Epoxy Glue
Slow Cyanoacrylate Glue (Cyno)
Foam Padding
Items Required
Equipment:
1 x Transmitter and Receiver
5 x Standard or Small Servos IC version - 4 x Standard or Small Servos Electric Version
2 x 200mm Servo Extension Leads
1 x 200mm Y-Lead
Electric Version
1 x Overlander 5045/10 Thumper or
Equivalent
1 x Electronic Speed-controller
1 x Suitable Propeller and Propeller Adapter
1 x Battery 14.8v 4s 3300-4250mAh
18.5v 5s 3300mAh
IC Version:
1 x 46-55 Size Model Engine
1 x Suitable Propeller
1 x Receiver Battery
1m Fuel Tube
1 x Fuel Filter
Some pictures throughout this manual may be of the prototype model and some details may now have
changed. If you have any questions please contact us [e-mail].

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Building Your Double Trouble
1. Start by glueing all of the hinges in place using CA Glue. Medium or Thick Slow set is best.
2. Check for any wrinkles in the covering and using a lm iron shrink these back so the lm is tight.
3. Install the control horns on to the Ailerons and also the upper and lower aileron connector plates.
You can trim down the plates to make sure they do not protrude through the covering if you wish and also
drill a small hole in the plate where it inserts in to the wing to give the 5 minute epoxy can grab through
the connector. These connectors go under the top wing and on top of the bottom wing. Servo horns go on
the under side of the bottom wing and under the elevator and are held in place with the M2 x 12mm self
tapping screws.

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Building Your Double Trouble
4. Next is the rudder horn which is made up by using a M3 x 45mm screw, 2 x nylon adaptors, 2 x M3
Nuts and 2 washers. Thread the plastic adaptor to the end of the screw and then run a 3mm nut followed
by a washer to just past the middle of the screw. Put the assembly through the whole in the rudder and
then repeat the steps in reverse, washer, nut, plastic adaptor. Make sure it is centered and tighten the
nuts together. A small drop of thread lock or cyno will stop the nuts coming loose.

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Building Your Double Trouble
6. Connect the ailerons to the servo using the short push rods. You will need to either put a z-bend
in the push rod to suit your servo position or a 90 degree bend and use swing keeper to hold it on to the
servo arm, you can then do the nal adjustments using the metal quick link.
5. Installing the aileron servos. Remove the cover and cut the servo area to t your choice of servo.
Screw the servos in to the covers using the screws supplied with your servos. Make sure you centre the
servo and t the servo control arm. Use the string provided to pull the servo wires through the wing, you
may need servo extension leads depending on your servos. Screw the assembly in to place using 4 M2 x
12mm self tapping screws.

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Building Your Double Trouble
7. Landing gear. Put a wheel on the axle by removing the collet, the collet should be ush with the
end of the axle and the wheel should spin freely. Run a nut and then a washer on to the threaded section
and place the wheel inside the spat. Push the axle thread though the landing strut making sure it is on the
correct side and then add the other washer and nut and secure in place. Make sure the wheel still spins
freely and secure the nuts with a dab of cyno or thread lock to stop them coming loose.
8. The landing gear is held in place on the fuselage by four M4 x 20mm cap head screws and
washers.

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Building Your Double Trouble
9. Tail Feathers. First step is to place the tailplane in position and then mark and remove a triangular
section of the lm from both sides of the tail plane so that the glue can stick to the balsa correctly. Make
this slightly smaller on the top to the bottom as the n fairings are slightly smaller than the tail plane seat
on the fuselage. When cutting the lm cut approx 1mm inside of your marked line so no wood shows and
make sure not to cut the wood underneath as this could weaken the tailplane.
10. Make sure the tail plane sits square on the fuselage and then glue in place using 5 or 30 minute
epoxy and pin in place Fit the elevator control horn.

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Building Your Double Trouble
11. Once the tailplane is glued in place you can t the n and rudder again using either 5 or 30 minute
epoxy. Make sure the lower rudder hinge is located in place before gluing the assembly in place.
12. Offer the tail wheel assembly to the fuselage and mark the screw locations and pilot drill 2mm
holes and then t using the screws provided. Fit the rudder cradle to the rudder and secure in place using
the 2mm nut and bolt.

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Building Your Double Trouble
13. Make up the rudder pull pull system by tting a metal quick link on to the brass adaptor with a nut.
Put a metal ferrule on to the wire and then take the wire through the eyelet and then back through the
ferrule and loop it back through and tuck the end in to the ferrule and crimp the ferrule tight. Do this for
both sides but only at the rudder end for now.
14. Thread the cables through the pre-ftted tubes in the fuselage to the servo bay and then t the links
to the rudder. You may need to use a sharp knife to trim the lm carefully around the openings for both the
rudder and elevator controls. Fit the elevator control rod as shown in the picture.

1111
Building Your Double TroubleBuilding Your IC Double Trouble
1. IC Version. Install the T-mounts for the engine to the rewall, We used a OS 46AX with a 12x6
Gemfan prop in the prototype model. There is 3.5 degrees of side thrust built into the mount so the mount
make look like it is off centre. You will need to adjust the engine mount position to suit your motor. Use the
M4 x 20mm cap head screws to secure the engine to the mount.
2. Test mount the cowl and carefully cut out for the exhaust, plug and carb/needle valve. Always cut
the holes under size to start with and slowly make bigger to suit your engine.
3. Install the throttle push-rod assembly and then assemble and install the fuel tank, use the Velcro
straps to hold the tank in place. Plumb the engine to the tank with the fuel tube. Fit the cowling in place
with the 3x8mm self taping screws and t your propeller and spinner.

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Building Your Double Trouble
1. Electric Version. Screw the wooden motor mount on using the 4mm x 14mm cap head screws and
washers. Centre your motor on the mount and mark the bolt hole locations on the motor mounting plate
and then drill these to suit. Mount the brushless motor using the cap head screws and captive nuts on to
the centre line of the mount. The mount is off set to allow for 3.5 Degrees of side thrust.
3. Fit the cowl using the 3x8mm big head self tapping screws. If you want you can add an additional
cooling slot on the underside of the cowl to let the hot air out. Fit your prop and the spinner to nish off the
front section. We used a 13x6.5 Gemfan prop and suitable spinner on the prototype model.
Building Your Electric Double Trouble
2. Test t the cowl and adjust the motor position forwards or backwards to make sure the spinner
and prop clear the cowl. Temporally hold in place with bands so you test t the cowling. Once you have the
motor in the correct position you can glue the adjustable mount in place using 5 minute epoxy. We then
recommend running some medium C/A down all the motor mount joints and apply triangular balsa to
reinforce the joints.

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Building Your Double Trouble
15. Fit the upper wing supports using the M3 x 12mm Cap Head Screws.
16. Turn the model over and sit it on the wing supports and n, from here you can now t the rudder
and elevator servos. If you are building the IC version you can now install the throttle servo and switch to
the non exhaust side of the model in the pre cut hole.
17. Once the servos are installed you can nish of the rudder pull pull system by repeating the process
in the same way as before, make sure to pull them tight and try and get both sides the same length. The
elevator rod will need bending and cutting to suit your servo position and securing to the servo arm with a
swing keeper or you can make a z-bend.

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Building Your Double Trouble
18. Bolt the top wing in to position on the centre struts using the M3 x 12mm cap head bolts and
washers, these can be fully tightened at this stage (if you wish you could t m3 nylock nuts for added
security but this will add to the assembly time at the eld but a good idea if you are leaving it assembled)
19. Screw the outer wing struts in to place also using M3 x 12mm cap head bolts and washers but do
not fully tighten until the bottom wing is in place. These should rake backwards towards the tail.

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Building Your Double Trouble
20. Next install the lower wing and secure using the M8 Thumb screws, line up the outer wing struts
and secure in place with the M3 x 12mm Cap head screws and washers. You can now fully tighten all the
bolts for the wing struts.
21. Make sure the ailerons are all level and connect up the lower and upper ailerons with the control
rods supplied. Cut and bend to suit and secure in place using the swing keeper and metal quick link. Make
sure both sides match and adjust if necessary.
Prototype model shown with an uncovered lower wing.

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Building Your Double Trouble
23. Final Setup.
Control throws for rst ight.
Aileron 8mm each way
Elevator 8mm each way
Rudder 20mm each way
You can increase these to suit your ying style after initial test ight are done.
Happy Flying and Landings, Mark Tilbury.
Centre of Gravity.
The C of G is set between 11 and 12cm back from the leading edge of the top wing. This can be adjusted
to suit after initial ights. If you need to add nose weight do this under the motor mount as far forwards as
possible
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22. The pilot, screen and fairing are optional parts to t. The screen needs to be cut to suit and we
added some red trim to the back of the screen to nish it off. Secure the screen and fairing in place using
Zap-A-Dap-A-Goo directly to the lm covering. Epoxy the pilot in place.

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Building Your Double Trouble
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Century UK LTD.
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Castle Road
Sittingbourne
KENT
ME10 3AE
United Kingdom
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MADE IN VIETNAM